2013년 미국불임학회(ASRM) P-1260 Which is better in IVF cycles of high responder? : all cryo or fresh embryo transfer. (높은 난소 기능을 가진 환자에서 시험관 시술에서 해당 주기에 이식하는 것이 좋은가 모두 동결시키는 것이 좋은가?)

I.H. PARK1, H.G. Sun1, J.H. Lee1, K.H. Lee1, J.D. Jo2 and G.H. Jeon3.
1 Mamapapa&baby OB&GY, 1367-5 Hwashin building 4th floor Dal-dong, Nam-gu Ulsan, Korea, 680-805; 2Ellemedi OB&GY, Dongjeong-dong 540 Changwon, Korea, 641-490 and 3Inje University, Haeundae Paik Hospital, Haeundaero 875, Haeundae-Gu Busan, Korea, 612-030.

OBJECTIVE

Recently, with the advances of the embryo cryopreservation techniques, some studies showed that the use of frozen-thawed embryo transfer (FET) significantly improved in vitro fertilization (IVF) outcomes compared with fresh embryo transfer (ET). However, some clinicians still prefer fresh ET to FET due to experience of better outcomes with fresh ET. The purpose of this study is to compare IVF outcomes between fresh ET and FET after cryopreservation of all embryos in high responders.

DESIGN

Retrospective study

MATERIALS AND METHODS

We retrospectively reviewed 717 patients experiencing high response (oocytes≥20) with low starting dose of rFSH (150 IU or less) in controlled ovarian hyperstimulation (COH) IVF cycles from January 2006 to December 2012. Three groups of patients were formed. Group I : fresh ET with 20≤oocytes<30, Group II : fresh ET with oocytes≥30, Group III : FET with oocytes≥20.

RESULTS

In each group, age, number of transferred embryos, percentage of top quality embryo reflected no differences. Group I (fresh-high responder) had significantly higher ongoing pregnancy rate (PR) than Group III (all cryo-FET) [51.8%(244/471) vs. 39.9%(61/153), P=0.007]. Group II (fresh-very high responder) had similar ongoing PR with Group III (all cryo-FET) [43.0%(40/93) vs. 39.9%(61/153), P=0.49]. Group I (fresh-high responder) had significantly higher ongoing PR than Group II (fresh-very high responder) [51.8%(244/471) vs. 43.0%(40/93), P=0.03].

CONCLUSION

In this study, ongoing pregnancy rate of fresh ET in high responders (20≤oocytes<30) was better than that of FET after cryopreservation of all embryos. However, pregnancy rate of fresh ET in very high responders (oocytes≥30) was similar with FET after cryopreservation of all embryos, but decreased as compared with high responders. In conclusion, in case of very high responders, fresh ET has no benefit on PR, but only has high risk of OHSS. Therefore, clinicians must consider FET after cryopreservation of all embryos in very high responders.